org.nd4j.linalg.inverse.InvertMatrix Maven / Gradle / Ivy
package org.nd4j.linalg.inverse;
import org.apache.commons.math3.linear.LUDecomposition;
import org.apache.commons.math3.linear.RealMatrix;
import org.nd4j.linalg.api.ndarray.INDArray;
import org.nd4j.linalg.checkutil.CheckUtil;
/**
* Created by agibsoncccc on 11/30/15.
*/
public class InvertMatrix {
/**
* Inverts a matrix
* @param arr the array to invert
* @return the inverted matrix
*/
public static INDArray invert(INDArray arr, boolean inPlace) {
if (!arr.isSquare()) {
throw new IllegalArgumentException("invalid array: must be square matrix");
}
//FIX ME: Please
//int[] IPIV = new int[arr.length() + 1];
//int LWORK = arr.length() * arr.length();
//INDArray WORK = Nd4j.create(new double[LWORK]);
//INDArray inverse = inPlace ? arr : arr.dup();
//Nd4j.getBlasWrapper().lapack().getrf(arr.size(1),arr.size(0),inverse, arr.size(0),IPIV,0);
//Nd4j.getBlasWrapper().lapack().getri(arr.size(0),inverse,arr.size(0),IPIV,WORK,LWORK,0);
RealMatrix rm = CheckUtil.convertToApacheMatrix(arr);
RealMatrix rmInverse = new LUDecomposition(rm).getSolver().getInverse();
INDArray inverse = CheckUtil.convertFromApacheMatrix(rmInverse);
if (inPlace)
arr.assign(inverse);
return inverse;
}
}